CN Patent No. 201606557U discloses that a conventional switching valve is installed in a body of a faucet assembly. The conventional switching valve includes a sleeve member and a plug member sliding along the sleeve member. In a normal operation state, water flows out of an outlet of the faucet assembly via the sleeve member, the plug member, a gap between an upper O ring and an upper valve seat of the plug member. Accordingly, when a lever of a spray head is operated, a water pressure in the switching valve changes so that the plug member slides downward, such that the upper O ring is biased against the upper valve seat, thus stopping a water supply from the faucet assembly. In the meantime, the water flows to the spray head through the sleeve member and a clearance between a lower O ring and a lower valve seat.
However, such a conventional switching valve still has the following disadvantages:
1. The plug member is hollow so that a chamber is defined in the plug member and two sets of holes formed around the chamber so as to flow water. But the plug member is metal formed and machined at high cost.
2. The upper O ring is forced by the water pressure, thus causing a deformation. In addition, water leaks from the gap between the upper O ring and the upper valve seat easily, thus having a water leakage from the faucet assembly.
3. As changing water supply from a faucet mode to a spray head mode, the plug member moves to the spray head quickly, so the upper O ring of the plug member collides the upper valve seat to result in vibration and noises.
4. As changing water supply from a spray head mode to a faucet mode, the flow capacity decreases to cause a back pressure, so the plug member switches to the spray head and the faucet assembly, hence the plug member swings constantly. Also, when an inflow pressure is not stable, the plug member vibrates as well.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.